PT-141 10mg

Buy high-purity PT-141 (10mg) in Australia. Third-party lab tested at >99% purity. Australian-domestic shipping, AUD pricing, supplied for laboratory research use only.

About PT-141

PT-141, also known as bremelanotide, is a synthetic cyclic heptapeptide melanocortin receptor agonist developed at Palatin Technologies in the early 2000s as a structurally optimised analogue of Melanotan-2. By removing the C-terminal lysine amide of MT-2 and retaining the cyclic Asp-Lys lactam bridge, PT-141 was engineered to preferentially activate the central melanocortin-4 receptor (MC4R) while reducing activity at MC1R and the associated melanogenic effects.

In published research, PT-141 has become one of the most extensively characterised MC4R-preferring research peptides, with study interest concentrated on central nervous system pathways relevant to sexual function and the broader pharmacology of the MC3R/MC4R subtypes.

Optic Labs supplies PT-141 as a lyophilised powder in 10mg research vials, third-party HPLC tested to >99% purity. The product is distributed Australian-domestic from Sydney, NSW, for in vitro and laboratory research applications. PT-141 is supplied strictly for laboratory research, development or analytical use and is not intended for human consumption.

Product specifications

• Compound: PT-141 (bremelanotide)
• CAS number: 189691-06-3
• Molecular formula: C₅₀H₆₈N₁₄O₁₀
• Molecular weight: ~1025.16 g/mol
• Sequence: Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-OH (cyclic heptapeptide)
• Form: Lyophilised powder
• Purity: >99% by HPLC
• Available size: 10mg vial
• Storage: 2–8°C, protect from light. Reconstituted: 2–8°C, used within 30 days.
• Origin: Manufactured to research-grade specifications, third-party HPLC verified
• Shipping: Australia-wide domestic dispatch from Sydney, NSW

Research background

PT-141 was developed by Palatin Technologies as a follow-on to the University of Arizona's MT-2 research programme. Where MT-2 is a non-selective pan-melanocortin agonist, PT-141 was engineered through C-terminal modification to retain MC4R activity while reducing the MC1R-mediated melanogenic effects.

The compound has been characterised extensively in receptor pharmacology, behavioural neuroscience and clinical research, and was approved by the US FDA in 2019 under the trade name Vyleesi for hypoactive sexual desire disorder in premenopausal women — making it the most clinically validated melanocortin research peptide currently available.

• MC4R-preferring receptor pharmacology: in receptor-binding and cAMP accumulation assays, PT-141 acts as an agonist at MC3R and MC4R with reduced relative activity at MC1R compared with MT-2, supporting its use as a research tool for probing MC4R-specific signalling.
• Central pathways of sexual behaviour: in published rodent and primate research, MC4R activation in the medial preoptic area and paraventricular nucleus has been investigated as a central mechanism for proceptive and consummatory sexual behaviour, with PT-141 used as the principal MC4R-preferring research probe.
• Hypothalamic signalling: in animal-model research, PT-141 has been examined for its effects on hypothalamic dopamine and oxytocin release, providing a candidate downstream mechanism for its observed behavioural effects.
• Cardiovascular research: in published clinical and preclinical research, MC4R activation has been studied for effects on blood pressure and heart rate, with PT-141 used as a tool to characterise the magnitude and time course of these responses.
• Energy balance research: in rodent hypothalamic studies, MC4R activation has been examined for effects on food intake and body weight in animal models, building on the genetic literature linking MC4R to energy homeostasis.
• Comparative melanocortin pharmacology: PT-141 is widely used alongside MT-2, NDP-α-MSH and selective MC4R antagonists in research designs comparing the contributions of each melanocortin subtype to a given functional outcome.
• Inflammation research: in cell-culture studies, MC3R/MC4R-preferring agonists have been examined for anti-inflammatory and immunomodulatory effects, complementing the MC1R-focused inflammation literature.

For a plain-language overview of peptides, see our what are peptides explainer. Researchers working with reconstitution should also reference our peptide reconstitution guide, and for laboratory injection protocols our subcutaneous injection protocol article.

Reconstitution and handling

PT-141 is supplied as a lyophilised powder and must be reconstituted with bacteriostatic water before use in any laboratory protocol. A common laboratory approach for the 10mg vial is reconstitution in 2ml of bacteriostatic water to yield a 5mg/ml working stock, or in 1ml for a 10mg/ml stock.

The bacteriostatic water should be drawn into a sterile syringe and injected slowly down the inside wall of the lyophilised vial, allowing the peptide cake to dissolve passively rather than through agitation. Reconstituted PT-141 should be aliquoted, refrigerated at 2–8°C and protected from light, with research stocks typically used within 30 days.

For dilution maths across alternative volumes, see our reconstitution calculator guide. For long-term storage protocols, see our peptide storage guide.

Commonly stacked research peptides

In published research and laboratory protocols, PT-141 is examined alongside other melanocortin and central-nervous-system research compounds:

• Melanotan-2 — non-selective melanocortin agonist studied alongside PT-141 to dissect MC1R versus MC4R contributions to a given research outcome.
• Selank — anxiolytic heptapeptide co-investigated with PT-141 in central nervous system and stress-axis research designs.
• Semax — nootropic peptide examined alongside PT-141 in studies probing dopaminergic and central neurotransmitter pathways.
• DSIP — delta sleep-inducing peptide co-studied in research on central regulation of arousal and behaviour.
• CJC-1295 + Ipamorelin — GH-axis research blend examined in parallel with PT-141 in studies of hypothalamic peptide signalling.

For broader context on combined research designs, see our peptide research stacks overview.

Frequently asked questions

Is PT-141 legal in Australia?

PT-141 (bremelanotide) is not currently registered with the Therapeutic Goods Administration (TGA) for any therapeutic indication in Australia, even though the compound has been approved in some other jurisdictions. Optic Labs supplies PT-141 strictly as a research chemical for in vitro and preclinical laboratory research — not for human consumption, clinical use or any therapeutic application.

For a full overview of how the TGA treats research peptides in Australia, see our peptide legality and TGA compliance guide.

What is PT-141?

PT-141 is a synthetic cyclic heptapeptide melanocortin receptor agonist with preferential activity at MC4R. It was developed at Palatin Technologies as an MC4R-preferring analogue of Melanotan-2, with reduced activity at the pigmentation-related MC1R subtype. For a plain-language overview of peptides, see our what are peptides explainer.

What does PT-141 do in published research?

In published research, PT-141 is studied for its effects on MC3R/MC4R receptor signalling, central nervous system pathways relevant to sexual behaviour, hypothalamic dopamine and oxytocin release, cardiovascular parameters such as blood pressure, and food intake regulation in rodent models. These observations are research findings only and do not constitute therapeutic claims.

How does PT-141 compare with Melanotan-2 in research?

PT-141 and Melanotan-2 share the same cyclic Asp-Lys core. PT-141 differs in that the C-terminal residue is a free carboxylate rather than a lysine amide, which biases its activity toward MC4R and away from MC1R. In research settings PT-141 is used as the more MC4R-selective probe, while MT-2 is used when broad melanocortin agonism is required.

How is PT-141 supplied?

Optic Labs supplies PT-141 as a lyophilised powder in 10mg glass research vials. Each vial is sealed with a tamper-evident closure. Certificates of analysis showing HPLC purity testing are available on request.

How much bacteriostatic water do I mix with a 10mg PT-141 vial?

For a 10mg vial, 2ml of bacteriostatic water yields a 5mg/ml working stock; 1ml yields a 10mg/ml stock; 5ml yields a 2mg/ml stock. Choose a volume based on the concentrations required by the research protocol. For a worked example with unit conversions, see our reconstitution calculator guide.

How should reconstituted PT-141 be stored?

Reconstituted PT-141 should be stored at 2–8°C, protected from light, and used within approximately 30 days. For longer-term storage, aliquoting and freezing at −20°C or below is preferred to limit freeze-thaw degradation. Full handling protocols are covered in our peptide storage research guide.

Where does Optic Labs ship to?

Optic Labs ships Australia-wide from Sydney, NSW. Standard dispatch is next business day on orders received before the daily cut-off. International shipping is not currently offered.

Legal disclaimer

All products on this site are supplied for laboratory research, development or analytical use only. They are not for human consumption, clinical use, or any diagnostic, cosmetic or veterinary application. These products and statements have not been evaluated by the Therapeutic Goods Administration (TGA) or the APVMA and are not intended to diagnose, treat, cure or prevent any disease.

Optic Labs is not a compounding pharmacy or manufacturing facility as defined under the Therapeutic Goods Act 1989, and is not a registered provider of scheduled medicines or therapeutic goods.